Outlook gets stuck on "Processing" due to add-ins, profile corruption, or data file issues. 1. Start by checking add-ins—launch Outlook in Safe Mode and disable them one by one. 2. Repair or rebuild the profile via Control Panel > Mail > Show Profiles by creating a new one. 3. Use ScanPST.exe or ScanOST.exe to fix corrupted PST/OST files. 4. Reset the navigation pane with outlook /resetnavpane command. These steps usually resolve the issue quickly without technical expertise.

Outlook getting stuck on "Processing" is a common issue, especially after updates or when dealing with large mailboxes. The good news is that most cases can be resolved without too much hassle — you just need to know where to start.

Check for Add-ins Causing the Problem

Add-ins are one of the top reasons Outlook gets stuck during startup. Some third-party tools or outdated plugins can interfere with normal loading.

• Try launching Outlook in Safe Mode (press Ctrl while opening it, or run outlook /safe from Run).
• If Outlook loads fine in Safe Mode, the issue is likely an add-in.
• Go to File > Options > Add-ins, and disable them one by one to find the culprit.
• You can also use the built-in "Manage COM Add-ins" dropdown at the bottom of that page to disable all temporarily.

Not all add-ins are obvious, so test disabling them even if they seem harmless — like toolbars or integration apps.

Repair or Rebuild the Profile

A corrupted Outlook profile can cause many issues, including the processing screen freeze. Recreating or repairing the profile often helps.

Here’s how to do it:

• Open Control Panel > Mail > Show Profiles
• Click Add, create a new profile, and set it as default
• Then, restart Outlook using this new profile

If that works, you can gradually add back your accounts and settings.
For Exchange or Microsoft 365 accounts, make sure you’re signed into the same Microsoft account — the mailbox should sync automatically.

Deal with Corrupted Data Files

Sometimes the PST or OST file that stores your emails is damaged. Outlook might hang trying to access it.

• Use the built-in ScanPST.exe tool (for PST) or ScanOST.exe (for OST)
• You can find these tools in the Office installation folder — usually under C:\Program Files\Microsoft Office\root\OfficeXX (XX being your version)
• Make a backup before running repairs, just in case

If the file is too broken, you may need to restore from a backup or let Outlook rebuild the OST by deleting it and letting it redownload data from the server.

Tweak Settings or Reset Navigation Pane

Another sneaky cause is a messed-up navigation pane — yes, really. This is what controls the left sidebar with folders and calendar.

• Close Outlook
• Press Win R, type outlook /resetnavpane, and hit Enter
• This resets the sidebar layout and often fixes the processing loop

This doesn’t delete any data — just resets UI settings. Worth trying early because it's quick and safe.

Fixing Outlook stuck on "Processing" usually comes down to profiles, add-ins, or data files. Try these steps one by one — most of the time, you’ll be back up within 10–15 minutes. Doesn’t require tech wizardry, just a bit of patience.

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